Quantitative and qualitative changes in the mitochondria in hepatocytes during postnatal development of male rats

1. Changes in certain kinetic properties (Vmax. and apparent Km) of hepatic microsomal mixed-function oxidases have been studied as a function of postnatal development and maturation in male rats. 2. Microsomal cytochrome P-450 content changed only slightly between 1 and 12 weeks of age. 3. Aniline hydroxylase activity (Vmax.) increased abruptly between 1 and 2 weeks of age to greater than adult activities and then returned to a plateau value between 4½ and 12 weeks of age. Ethylmorphine demethylase activity remained low and relatively constant between 1 and 3 weeks of age and then increased markedly (∼100%) between 3 and 4½ weeks. 4. The apparent Michaelis constant (Km) for aniline hydroxylation increased almost linearly with time between 1 and 6 weeks of age and tended to reach a plateau value thereafter. The apparent Km for ethylmorphine demethylation increased between 1 and 3 weeks of age and then decreased abruptly to a constant value between 6 and 12 weeks. 5. The data indicate that developmental changes in the activity of these microsomal oxidases do not correlate temporally with each other or with changes in microsomal cytochrome P-450 content. 6. The most dramatic changes in enzyme activity were associated with early development (1–3 weeks) and weaning (3–4 weeks). 7. Changes in weight of seminal vesicle, a criterion of sexual maturation in male rats, were most prominent between 6 and 8 weeks of age and thus appeared to be separated in time from the prominent changes in enzyme activity.

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Glutamate Neonatal Excitotoxicity Modifies VEGF-A, VEGF-B, VEGFR-1 and VEGFR-2 Protein Expression Profiles During Postnatal Development of the Cerebral Cortex and Hippocampus of Male Rats

Journal of Molecular Neuroscience ◽

10.1007/s12031-017-0952-7 ◽

2017 ◽

Vol 63 (1) ◽

pp. 17-27 ◽

Cited By ~ 8

Author(s):

Jose Luis Castañeda-Cabral ◽

Carlos Beas-Zarate ◽

Graciela Gudiño-Cabrera ◽

Monica E. Ureña-Guerrero

Keyword(s):

Cerebral Cortex ◽

Protein Expression ◽

Postnatal Development ◽

Expression Profiles ◽

Male Rats ◽

Protein Expression Profiles

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Changes in RFamide-Related Peptide-1 (RFRP-1)-Immunoreactivity During Postnatal Development and the Estrous Cycle

Endocrinology ◽

10.1210/en.2014-1274 ◽

2014 ◽

Vol 155 (11) ◽

pp. 4402-4410 ◽

Cited By ~ 14

Author(s):

Sara R. Jørgensen ◽

Mille D. Andersen ◽

Agnete Overgaard ◽

Jens D. Mikkelsen

Keyword(s):

Postnatal Development ◽

Estrous Cycle ◽

Third Ventricle ◽

Female Rats ◽

Male Rats ◽

Relative Distribution ◽

Gonadotropin Secretion ◽

Related Peptide

Abstract GnRH is a key player in the hypothalamic control of gonadotropin secretion from the anterior pituitary gland. It has been shown that the mammalian counterpart of the avian gonadotropin inhibitory hormone named RFamide-related peptide (RFRP) is expressed in hypothalamic neurons that innervate and inhibit GnRH neurons. The RFRP precursor is processed into 2 mature peptides, RFRP-1 and RFRP-3. These are characterized by a conserved C-terminal motif RF-NH2 but display highly different N termini. Even though the 2 peptides are equally potent in vitro, little is known about their relative distribution and their distinct roles in vivo. In this study, we raised an antiserum selective for RFRP-1 and defined the distribution of RFRP-1-immunoreactive (ir) neurons in the rat brain. Next, we analyzed the level of RFRP-1-ir during postnatal development in males and females and investigated changes in RFRP-1-ir during the estrous cycle. RFRP-1-ir neurons were distributed along the third ventricle from the caudal part of the medial anterior hypothalamus throughout the medial tuberal hypothalamus and were localized in, but mostly in between, the dorsomedial hypothalamic, ventromedial hypothalamic, and arcuate nuclei. The number of RFRP-1-ir neurons and the density of cellular immunoreactivity were unchanged from juvenile to adulthood in male rats during the postnatal development. However, both parameters were significantly increased in female rats from peripuberty to adulthood, demonstrating prominent gender difference in the developmental control of RFRP-1 expression. The percentage of c-Fos-positive RFRP-1-ir neurons was significantly higher in diestrus as compared with proestrus and estrus. In conclusion, we found that adult females, as compared with males, have significantly more RFRP-1-ir per cell, and these cells are regulated during the estrous cycle.

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Spatially Selective Pruning of Primary Gonadotropin Releasing-Hormone (GnRH) Neuronal Dendrites Occurs during Postnatal Development in Male Rats.

10.1210/endo-meetings.2010.part1.p5.p1-206 ◽

2010 ◽

pp. P1-206-P1-206

Author(s):

N. Ybarra ◽

P.J. Hemond ◽

M.P. O’Boyle ◽

K.J. Suter

Keyword(s):

Postnatal Development ◽

Gonadotropin Releasing Hormone ◽

Male Rats ◽

Releasing Hormone ◽

Neuronal Dendrites

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Postnatal development of gastric aromatase and portal venous estradiol-17β levels in male rats

Journal of Endocrinology ◽

10.1530/joe-13-0074 ◽

2013 ◽

Vol 218 (1) ◽

pp. 117-124 ◽

Cited By ~ 8

Author(s):

Hiroto Kobayashi ◽

Saori Yoshida ◽

Ying-Jie Sun ◽

Nobuyuki Shirasawa ◽

Akira Naito

Keyword(s):

Gastric Mucosa ◽

Portal Vein ◽

Postnatal Development ◽

Liver Weight ◽

Estrogen Receptor Α ◽

Male Rats ◽

Mrna Levels ◽

Gastric Parietal Cells ◽

Estradiol 17Β

Gastric parietal cells synthesize and secrete estradiol-17β (E2) into gastric veins joining the portal vein, and a large amount of gastric E2first binds to its receptors in the liver. However, the role of the gastric E2is not entirely clear during postnatal development. The objective of this study was to reveal the onset of aromatase and other steroid-synthesizing enzymes in the gastric mucosa; to determine the period of rising E2levels in the portal vein; and to further understand the relationship between gastric E2and liver estrogen receptor α (ERα). The immunoblot bands and the immunohistochemistry of gastric mucosa revealed that aromatase protein began to express itself at 20 days and then increased in the levels of aromatase protein from 20 days onward. Expression of mRNAs for gastric aromatase (Cyp19a1) and other steroid-synthesizing enzymes, 17α-Hydroxylase (Cyp17a1) and 17β-hydroxysteroid dehydrogenase (HSD17b3), also increased similar to the increment of aromatase protein. Portal venous E2levels were elevated after 20 days and increased remarkably between 23 and 30 days, similar to gastric aromatase mRNA levels. The E2level was approximately three times higher at 40 days than that at 20 days. The liver weight andEsr1levels began to increase after 20 days and the increment was positively correlated with the change of portal venous E2levels. These findings suggest that some changes may occur around 20 days to regulate the gastric E2synthesis and secretion.

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Postnatal development and sublobular distribution of cytochrome P-450 in rat liver: a microphotometric study.

Journal of Histochemistry & Cytochemistry ◽

10.1177/41.3.8429202 ◽

1993 ◽

Vol 41 (3) ◽

pp. 397-400 ◽

Cited By ~ 13

Author(s):

J Watanabe ◽

Y Asaka ◽

S Kanamura

Keyword(s):

Postnatal Development ◽

Rat Liver ◽

Perinatal Period ◽

Postnatal Growth ◽

Male Rats ◽

Heterogeneous Distribution ◽

Liver Lobule ◽

Subsequent Period ◽

The Difference ◽

Cytochrome P 450

To study the process of expression of cytochrome P-450 (P-450) in hepatocytes during development, we measured microphotometrically the P-450 content in periportal and perivenular hepatocytes of male rats during peri- and postnatal growth. From Day 19 of gestation to Day 5 after birth, P-450 content in both periportal and perivenular hepatocytes increased markedly (periportal 1046%; perivenular 819%). The content in periportal hepatocytes remained unchanged from 5 to 20 days of age, and increased slightly (24%) from 20 to 45 days of age. However, the content in perivenular hepatocytes increased progressively (105%) between 5 and 45 days of age. The difference in P-450 content became apparent between periportal and perivenular hepatocytes after 7 days of age. The content in periportal or perivenular hepatocytes reached the adult level at 45 days of age. Therefore, the perinatal period is the time at which a marked increase in P-450 occurs in hepatocytes throughout the liver lobule. The subsequent period before weaning is the time at which the sublobular heterogeneous distribution of P-450 appears. The period after weaning is the time at which a slight increase in P-450 content in periportal hepatocytes and a marked increase in the enzyme in perivenular hepatocytes takes place.

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